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                                  UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549

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                                    FORM 6-K

       REPORT OF FOREIGN PRIVATE ISSUER PURSUANT TO RULE 13a-16 or 15d-16
                    UNDER THE SECURITIES EXCHANGE ACT OF 1934

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                          Date of Report: March 6, 2006

                               CEMEX, S.A. de C.V.
             (Exact name of Registrant as specified in its charter)

                                   CEMEX Corp.
                 (Translation of Registrant's name into English)

                              United Mexican States
                 (Jurisdiction of incorporation or organization)

          Av. Ricardo Margain Zozaya #325, Colonia Valle del Campestre
                     Garza Garcia, Nuevo Leon, Mexico 66265
                    (Address of principal executive offices)


Indicate by check mark whether the registrant files or will file annual reports
under cover Form 20-F or Form 40-F.

Form 20-F   X        Form 40-F
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Indicate by check mark whether the registrant by furnishing the information
contained in this Form is also thereby furnishing the information to the
Commission pursuant to Rule 12g3-2(b) under the Securities Exchange Act of 1934.

Yes                  No   X
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If "Yes" is marked, indicate below the file number assigned to the registrant in
connection with Rule 12g3-2(b):

N/A
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================================================================================ Contents 1. Press release, dated March 6, 2006, announcing the expansion of its Yaqui cement plant in Sonora, Mexico (attached hereto as exhibit 1).

SIGNATURE Pursuant to the requirements of the Securities Exchange Act of 1934, CEMEX, S.A. de C.V. has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized. CEMEX, S.A. de C.V. ---------------------------- (Registrant) Date: March 6, 2006 By: /s/ Rafael Garza -------------------------------------- ------------------------- Name: Rafael Garza Title: Chief Comptroller

EXHIBIT INDEX EXHIBIT NO. DESCRIPTION - ----------- ----------- 1. Press release, dated March 6, 2006, announcing the expansion of its Yaqui cement plant in Sonora, Mexico.

                                                                       Exhibit 1
                                                                       ---------

     Media Relations            Investor Relations          Analyst Relations
       Jorge Perez              Abraham Rodriguez             Ricardo Sales
    (52-81) 8888-4334           (52-81) 8888-4262            (212) 317-6008


                             C E M E X        |  100
                      Building the future(TM) | YEARS


                          CEMEX TO INVEST $210 MILLION
                          TO EXPAND YAQUI CEMENT PLANT

MONTERREY, MEXICO, March 6, 2006 - CEMEX, S.A. de C.V. (NYSE: CX) announced
today that it intends to begin construction of a new kiln at its Yaqui Cement
Plant in Sonora, Mexico. The construction is expected to be completed in 2007.
The total value of the investment, which will extend over a two-year timeframe,
is approximately $210 million.

The current production of the Yaqui Plant is approximately 1.35 million tons per
year, and will be increased by an additional 1.8 million tons a year when
completed.

"The strong demand for cement in the region drove our decision to expand CEMEX's
Northwest Mexico facility. This investment reflects the Company's confidence in
the strength of the Mexican economy and the continued growth of the housing
market in the Northwest region. We expect this investment to provide a return on
capital employed well in excess of 10%, as we are well-positioned to capitalize
on the increasing demand for cement products in Mexico," said Francisco Garza,
President of CEMEX North America.

CEMEX is a growing global building solutions company that provides high quality
products and reliable service to customers and communities in more than 50
countries throughout the world. Commemorating its 100th anniversary in 2006,
CEMEX has a rich history of improving the well-being of those it serves through
its efforts to pursue innovative industry solutions and efficiency advancements
and to promote a sustainable future. For more information, visit www.cemex.com.

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